Diversity and distribution of Victoria Land biota

Understanding the relationship between soil biodiversity and ecosystem functioning is critical to predicting and monitoring the effects of ecosystem changes on important soil processes. However, most of Earth's soils are too biologically diverse to identify each species present and determine their functional role in food webs. The soil ecosystems of Victoria Land (VL) Antarctica are functionally and biotically simple, and serve as in situ models for determining the relationship between biodiversity and ecosystem processes. For a few VL taxa (microarthropods, nematodes, algae, mosses and lichens), species diversity has been intensively assessed in highly localized habitats, but little is known of how community assemblages vary across broader spatial scales, or across latitudinal and environmental gradients. The composition of tardigrade, rotifer, protist, fungal and prokaryote communities is emerging. The latter groups are the least studied, but potentially the most diverse. Endemism is highest for microarthropods and nematodes, less so for tardigrades and rotifers, and apparently low for mosses, lichens, protists, fungi and prokaryotes. Much of what is known about VL diversity and distribution occurs in an evolutionary and ecological vacuum; links between taxa and functional role in ecosystems are poorly known and future studies must utilize phylogenetic information to infer patterns of community assembly, speciation, extinction, population processes and biogeography. However, a comprehensive compilation of all the species that participate in soil ecosystem processes, and their distribution acrossregional and landscape scales is immediately achievable in VL with the resources, tools, and expertise currently available. We suggest that the soil ecosystems of VL should play a major role in exploring the relationship between biodiversity and ecosystem functioning, and in monitoring the effects of environmental change on soil processes in real time and space. (c) 2006 Elsevier Ltd. All rights reserved